For undecided voters, the gut rules

Most know - they just haven't told pollsters, or themselves, yet

Sens. Barack Obama and Hillary Rodham Clinton have been running for president for a year. They've dueled at a couple dozen debates, mugged for magazine covers and attracted a half million Facebook fans between them. They've been dissected by bloggers and journalists and endorsed by everybody from Barbra Streisand to the Grateful Dead to various Kennedys.

They've been the subject of more "Hardball" discussion than the human soul can endure.

So how could 18 percent of Californian Democrats still be undecided between the two, according to a Field Poll taken late last week? At this point, what could possibly help voters pick between the two today when they cast their ballots.

"What's really amazing is that 80 percent of the people have already decided," said Samuel Popkin, a professor of political science at UC San Diego and a pollster for several Democratic presidents. He is unaligned in this race. "The simple answer is that people haven't been paying attention until now."

Electoral dithering has not been unusual in the past month. In each of the four contested Democratic primaries or caucuses, at least 26 percent of the voters told exit pollsters that they didn't make up their mind until a week before they voted.

In New Hampshire - where the candidates had been living in their spare bedrooms for months - 17 percent of the voters didn't make up their mind until election day, according to an MSNBC exit poll.

But "make up their mind" is the wrong way to describe what voters are doing. They already have made up their mind; they just haven't felt like telling a pollster, said Jon A. Krosnick, a political science professor at Stanford University who is an expert on political psychology.

"If people say they're undecided, it really means that they're just uncertain," Krosnick said. "Primary elections are the hardest for voters because they usually like the candidates to some degree. The real issue for them may be which candidate is more electable."

The truly undecided voter is rare, say those who study the psychology of voting. Since neuroscientists say 90 percent of thought is unconscious, an undecided voter may have already decided - he just hasn't revealed his pick to himself yet.

Voters' ultimate decision depends on what issues they are framing the election around. And if those frames are conflicting as they enter the voting booth, the last one activated in a voter's mind will dominate, said George Lakoff, the UC Berkeley linguistics professor who has consulted many Democrats on shaping their message.

In the last moments, anything could light up a voter's frame, Lakoff and others said. It could be what a spouse or roommate says on the way out the door, or a person waving a sign on the street on the way to the polls.

Even "Yes We Can," a new song written by Black Eyed Peas member Will.I.Am that mashes up Obama's New Hampshire primary speech with various musicians singing along, could move voters, said Robb Willer, an assistant professor of sociology at UC Berkeley who studies political attitudes. The video has been viewed more than 10 million times since it was released Friday.

"With undecided voters who are really undecided, there is good reason to think that late advertising can affect them," Willer said.

In these final hours, Lakoff said, voters are less likely to evaluate candidates based on their stand on a particular policy, but more because of how they appear to them in other ways.

What are the candidates' values? Are they authentic? Do they communicate well? Can you identify with them?

"That's why Obama has been picking up, because he speaks to these questions," Lakoff said. "Clinton, on the other hand, has been offering her positions on issues."

But Popkin said voters who are concerned about an issue when they walk into the voting booth will trust their gut. If they're worried about the economy, for example, "they'll vote for the candidate they think can handle it," Popkin said.

So among voters who are thinking about specific issues as they vote today, Clinton may be more appealing, analysts said. "If the voter is looking at who is more aspirational and inspirational," Popkin said, "then it's Obama."